1. Field of the Invention
The present invention relates to a gear structure, and more particularly to a composite vibration reduction gear structure that is mounted in an image input and output device, to decrease noise during operation.
2. Description of the Related Art
A large-scale or small-scale device using the motor as its power supply often needs to co-operate with a reduction gear set to convert the high rotational speed output of the motor into a proper rotational speed.
For the large-scale device, couplers may be used to transmit the power between the motor, the reduction gear set, and the output shaft. The coupler may be made of vibration reduction material such as rubber. Thus, the coupler may reduce vibration and prevent noise from being produced during power transmission.
For the small-scale device, e.g., in the flatbed scanner or the sheet-fed scanner in the image input and output device, the motor may co-operate with the reduction gears and the belt to drive the scanning module. In the printer in the image input and output device, the motor may co-operate with the reduction gears to drive the printing head. The photocopier also uses cooperation of the motor with the reduction gears.
The image input and output device is a partial noise source in the office. Therefore, the design of the image input and output device already emphasizes the improvement of noise apparently. However, when the noise improvement design of the mechanisms everywhere reaches the limit, it is necessary to improve the detailed structures.
For power transmission, the motor may transmit the power of a high speed operation to the reduction gear set which may then transmit the power outward. During the transmission process, the elements may contact and hit each other, thereby producing vibration and noise. Thus, the contacts between the elements may be improved to reduce the vibration and noise during operation of the elements.
The primary objective of the present invention is to provide a vibration reduction gear structure of an image input and output device, wherein in the torque transmission path of the two gears, there is provided with a vibration reduction portion contacting the two gears. Thus, vibration produced between the two gears during operation may be absorbed, thereby preventing noise from being produced.
At least one of the two co-axially abutting gears is provided with the vibration reduction portion, and the other gear is rested on the vibration reduction portion. Thus, vibration producing between the two gears during operation may be absorbed, thereby preventing noise from being produced. The vibration reduction portion is made of material having a shock-absorbing feature, and may be integrally formed with or combined with the gear.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.